Typical vegetable oils and animal fats used in foods contain fatty acids which are predominantly 16 or 18 carbons long and contain zero to three double bonds. These are generally referred to as long chain triglycerides. Some oils such as rapeseed oil contain fatty acids having 20 or 22 carbons or higher.
Medium chain triglycerides (MCT's) are triglycerides made with saturated C.sub.6 to C.sub.10 fatty acids. These shorter chain triglycerides are metabolized differently from long chain triglycerides by the body because they are more water-soluble than long chain triglycerides. Because they hydrolyze rapidly and are absorbed via the portal vein, they provide a source of quick energy.
Several references disclose triglycerides containing medium chain and long chain fatty acids. For example, U.S. Pat. No. 3,353,964 of Seiden, issued Nov. 21, 1967, discloses a margarine oil made from corandomized triglycerides containing saturated short chain fatty acids having 6-14 carbon atoms and saturated long chain fatty acids having 20-22 carbon atoms. The triglycerides, a corandomized blend of hydrogenated rapeseed oil with coconut and/or palm kernel oil, are high in lauric acid.
U.S. Pat. No. 4,607,052 of Mendy et al., issued Aug. 19, 1986, discloses triglycerides of the formula: ##STR1## where R represents an acyl fragment of a polyunsaturated fatty acid containing 18 to 22 carbon atoms, the acyl fragment being capable of being oxidized, and where n represents an integer varying from 2 to 16. The triglycerides are used as nutritional supplements to provide a source of polyunsaturated fatty acids.
A synthetic therapeutic oil is disclosed in U.S. Pat. No. 3,450,819 of Babayan et al., issued Jun. 17, 1969. The oil is useful for treating humans suffering from malabsorption of fat. The oil comprises triglycerides having a major portion of medium chain (saturated C.sub.6 to C.sub.12) fatty acids, and a minor portion of essential fatty acids. The essential fatty acids are unsaturated fatty acids, primarily linoleic (C.sub.18:2), linolenic (C.sub.18:3), and arachidonic (C.sub.20:4).
U.S. Pat. No. 4,528,197 of Blackburn, issued Jul. 9, 1985, discloses a composition for enhancing protein anabolism in an hypercatabolic mammal. The composition is made of a nutritionally sufficient source of amino acids, carbohydrates and lipids, the lipids comprising a controlled triglyceride source which, on hydrolysis, yields both long chain fatty acids and medium chain fatty acids. One such fatty acid source disclosed is a structured lipid containing medium chain fatty acids (saturated C.sub.8, C.sub.10, and C.sub.12), and essential fatty acids.
Mok et al., "Structured Medium Chain and Long Chain Triglyceride Emulsions are Superior to Physical Mixtures in Sparing Body Protein in the Burned Rat", Metabolism, Vol . 33, No. 10, pp. 910-915, October 1984, describe an emulsion consisting of triglycerides composed of medium chain and long chain fatty acids in similar proportions used for sparing body protein in burned rats. The triglycerides were made from capric acid (C.sub.8:0), caprylic acid (C.sub.10:0), linoleic acid (C.sub.18:2), and other long chain fatty acids.
Maiz et al., "Protein Metabolism During Total Parenteral Nutrition (TPN) in Injured Rats Using Medium Chain Triglycerides," Metabolism, Vol. 33, No. 10, pp. 901-909, October 1984, disclose a lipid emulsion made from triglycerides containing 60% medium chain fatty acids and 40% long chain fatty acids said to improve protein utilization in injured rats. The medium chain fatty acids used are saturated C.sub.8 through C.sub.12, and the long chain fatty acids are derived from sunflower or safflower oil (which consist primarily of mixed triglycerides of linoleic and oleic fatty acid moieties).
European Patent Application 216,419 of Jandacek et al., published Apr. 1, 1987, relates to a nutritional fat suitable for use in enteral and parental products, consisting essentially of from about 50% to about 100% by weight of triglycerides having the formula: ##STR2## The R.sup.1 groups consist of saturated medium chain fatty acids with chain lengths of 7-11 carbon atoms, and the R.sup.2 group consists of 0-90% saturated C.sub.7 -C.sub.18 fatty acids, 0-90% oleic (C.sub.18:1), 10-100% linoleic (C.sub.18:2), and 0-10% linolenic (C.sub.18:3).
U.S. Pat. No. 2,874,056 of Drew, issued Feb. 17, 1959, discloses a triglyceride composition useful in margarines. The triglyceride is made from a combination of medium chain fatty acids (C.sub.8:0 through C.sub.12:0) and palmitic acid (C.sub.16:0).
The Captex 810 series of oils (Capital City Products, Dept. TR, P.O. Box 569, Columbus, Ohio 43216) contains random structure triglycerides that are made from mixtures of various ratios of long and medium chain fatty acids. The fatty acid compositions of these oils are as follows:
______________________________________ Fatty acid composition (weight %) of the Captex 810 series Linoleic Octanoic and Decanoic Captex series (C.sub.18:2) (C.sub.8:0 & C.sub.10:0) Other ______________________________________ 810A 10 80 10 810B 25 60 15 810C 35 46 19 810D 45 32 23 ______________________________________
None of these references discloses or suggests the reduced calorie fats of the present invention, or the benefits associated therewith. For example, the Seiden patent discloses a margarine oil high in lauric acid. The object is improved eating quality and heat resistance, not calorie reduction. Additionally, lauric acid is metabolized differently from the medium chain (saturated C.sub.6 to C.sub.10) fatty acids used in the present invention.
Moreover, the references by Mendy et al., Babayan et al., Blackburn, Jandacek et al., etc., relate to fats useful as nutritional supplements. The fats of the present invention, on the other hand, combine a calorie reduction benefit with good taste. The prior references also have fatty acid compositions different from those of the present invention.
It is, therefore, an object of the present invention to provide fat compositions that are reduced in calories when compared to typical chain length triglycerides.
It is another object of the present invention to provide reduced calorie fats that can be used to make food and beverage products having excellent textural and organoleptic properties.
These and other objects of the present invention will become evident from the disclosure herein.
All parts, percentages, and ratios used herein are by weight unless otherwise indicated.